TM 5-3805-254-20-1
ORGANIZATIONAL TROUBLEHSOOTING - CONTINUED
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
63.
REAR BRAKES DO NOT RELEASE - CONTINUED.
Step 2. Check treadle valve (1) for air pressure as follows: have assistant press down brake pedal (2),
check for exhaust of air pressure from valve vent (3) on bottom of treadle valve (1) when brake
pedal (2) is released.
a.If air pressure is not vented from valve vent (3) on bottom of treadle valve (1) when
brake pedal (2) is released, replace treadle valve (1) (page 2-1052).
b.If air pressure is vented from valve vent (3) on bottom of treadle valve (1) when brake
pedal (2) is released, go to step 3.
Step 3. Check front relay valve (4) for air pressure as follows: using 7/8-inch open-end wrench, loosen
output hose fitting (5) six turns. Have assistant press down brake pedal (2), listen for hissing
noise at output hose fitting (5).
a.If hissing noise is not heard at output fitting (5), replace front relay valve (4), notify
Direct Support Maintenance.
b.If hissing noise is heard at output hose fitting (5), go to step 4.
TA234911
2-336
